public void BoundingBoxSample()
{
    // 实例化一个包围盒对象，返回其中心点    
    Point3D point3D_L = new Point3D(1, 1, 1);
    Point3D point3D_U = new Point3D(101, 101, 101);
    BoundingBox boundingBox = new BoundingBox(point3D_L,point3D_U);
    Point3D center = boundingBox.Center;
    Console.WriteLine("包围盒对象的中心点为：" + center);// 包围盒对象的中心点为：{X=51.0,Y=51.0,Z=51.0}
}